The Las Conchas wildfire in New Mexico spread dangerously close to the Los Alamos National Laboratory this week, causing the evacuation of the town and the shutdown of the lab, which is the headquarters for US military research. The laboratory was created during World War II to develop the first atomic bomb for the Manhattan Project and houses highly sensitive materials. As a precaution, scientists are monitoring radioactivity in the air. The fire is the largest wildfire in the state's history, covering more than 100,000 acres.(Editor's Note: We will not post on Monday, July 4th, we'll see you again on Wednesday, July 6, 2011.) -Leanne Burden Seidel (34 photos total)

A vicious wildfire burns near the Los Alamos Laboratory in Los Alamos, N.M., on June 28, 2011. The Las Conchas fire spread through the mountains above the northern New Mexico town, driving thousands of people from their homes as officials at the government nuclear laboratory tried to dispel concerns about the safety of sensitive materials. (Jae C. Hong/Associated Press)

New Mexico National Guard member Pia Romero holds a map of the Las Conchas fire during a news conference in Los Alamos, N.M., on June 29, 2011. The wildfire 12 miles southwest of Los Alamos was 3 percent contained after burning across nearly 61,000 acres or 95 square miles. (Jae C. Hong/Associated Press) #

A NASA image taken by a crew member aboard the International Space Station, flying at an altitude of approximately 235 statute miles on June 27, 2011, shows the Las Conchas fire in the Jemez Mountains of the Santa Fe National Forest in north-central New Mexico. The fire is just southwest of Los Alamos National Laboratories. (NASA/Associated Press) #

Carissa Pittman consoles her daughter, Emily, 15, while her husband, Pete, in the car, and son, Allen, 21, prepare to leave Los Alamos, N.M., because of the wildfire on June 27, 2011. Thousands of residents calmly fled Monday from the mesa-top town that's home to the Los Alamos nuclear laboratory, ahead of an approaching wildfire. (Jane Phillips/The New Mexican via Associated Press) #

Flames from the Las Conchas fire burn in Los Alamos, N.M. in the Jemez Mountains on the morning of June 28, 2011. Fire managers said it was a "make or break day" for ensuring flames from the wildfire don't race into the northern New Mexico town that is home to a government nuclear laboratory that stores sensitive materials. (Eddie Moor/Albuquerque Journal via Associated Press) #

Los Alamos residents Ross Van Lyssel, left, and Steve Bowers watch flames from the Las Conchas fire in Los Alamos, N.M., on June 28, 2011. The vicious wildfire spread through the mountains above the northern New Mexico town, driving thousands of people from their homes as officials at the government nuclear laboratory tried to dispel concerns about the safety of sensitive materials. (Jae C. Hong/Associated Press) #

Wind battered flags located at a fire station at Diamond and Range roads in Los Alamos, N.M., flap in the breeze on June 27, 2011, after the fast-moving wildfire broke out in New Mexico and forced officials at the Los Alamos National Laboratory to close the site as residents nearby evacuated their homes. (Pat Vasquez-Cunningham/The Albuquerque Journal via Associated Press) #

A tree burns near Los Alamos, N.M., on June 29, 2011, as crews fight to keep the wildfire from reaching the country's premier nuclear-weapons laboratory and the surrounding community and as scientists sample the air for chemicals and radiological materials. (Jae C. Hong/Associated Press) #

A firefighter walks through heavy smoke from the Las Conchas fire near Los Alamos, N.M., on June 29, 2011. As crews fight to keep the wildfire from reaching the country's premier nuclear-weapons laboratory and the surrounding community, scientists are busy sampling the air for chemicals and radiological materials. (Jae C. Hong/Associated Press) #

A wave of smoke billows and fills a canyon as the Las Conchas, N.M. fire creeps into the canyon. The wildfire threatening the nation’s premier nuclear weapons laboratory and a community in northern New Mexico was poised Thursday to become the largest fire in state history. (Morgan Petroski/Albuquerque Journal via Associated Press) #

The top of a plume of smoke from the Las Conchas wildfire in the Jemez Mountains billows in the clouds, as seen from miles away in Rio Rancho, N.M., on June 26, 2011. Fire officials say the Las Conchas fire charred more than 3,500 acres since starting Sunday afternoon. Voluntary evacuations were issued for Los Alamos and White Rock. (Susan Montoya Bryan/Associated Press) #

Fire trucks patrol the western area of Los Alamos, N.M., a day after an evacuation order was issued because of the encroaching Las Conchas wildfire on June 28, 2011. New Mexico fire managers scrambled on Tuesday to reinforce crews battling a third day against an out-of-control blaze at the edge of one of the nation's top nuclear weapons production centers. (Craig Fritz/Reuters) #

The Morrison family, Dee, top left, Taylor, 4, right, Bob, and Jeni, center, pack up their belongings following a mandatory evacuation ordered for Los Alamos, N.M., as the rapidly growing Las Conchas wildfire approaches on June 27, 2011. The blaze, which began Sunday, had already destroyed 30 structures south of Los Alamos and forced the closure of the Los Alamos Nuclear Laboratory. (Craig Fritz/Associated Press) #

Gary Thayer takes out a cooler of food as he prepares to leave following the mandatory evacuation of Los Alamos, N.M., on June 27, 2011. Thousands of residents calmly fled the town that's home to the Los Alamos nuclear laboratory as the rapidly growing wildfire approached, sending up towering plumes of smoke, raining down ash and charring the fringes of the sprawling lab's property. (Craig Fritz/Associated Press) #

The Las Conchas Fire burns through a canyon on June 29, 2011 in Los Alamos, N,M. The government sent a plane equipped with radiation monitors over the Los Alamos nuclear laboratory as a 110-square-mile wildfire burned at its doorstep, putting thousands of scientific experiments on hold for days. (Morgan Petroski/The Albuquerque Journal via Associated Press) #

Threatened by the Las Conchas wildfire, residents wind their way by car along Diamond Drive following an evacuation order for Los Alamos, N.M., on June 27, 2011. Thousands of residents calmly fled the town that's home to the Los Alamos nuclear laboratory as a rapidly growing wildfire approached, sending up towering plumes of smoke, raining down ash, and charring the fringes of the sprawling lab's property. (Craig Fritz/Associated Press) #

Felina Trujillo, from Los Alamos, left, and her daughter Jenna Trujillo, 15, who both evacuated Las Alamos on Sunday, look for groceries in the donated food at the Food Depot in Sante Fe, N.M. on June 29, 2011. The Food Depot is making direct donation to evacuees. (Luis Sánchez Saturno/The New Mexican via Associated Press) #

The sun filters through thick smoke from a wildfire burning near Los Alamos, N.M., on June 27, 2011. Thousands of residents calmly fled the town that's home to the Los Alamos nuclear laboratory as a rapidly growing wildfire approached, sending up towering plumes of smoke, raining down ash and charring the fringes of the sprawling lab's property. The blaze, which began Sunday, had destroyed 30 structures south of Los Alamos and forced the closure of the lab. (Susan Montoya Bryan/Associated Press) #

Alex Lopez plays baseball with his sister Sugey while smoke generated by the Las Conchas fire covers the sky in Espanola, N.M. on June 29, 2011. As crews fight to keep the wildfire from reaching the country's premier nuclear-weapons laboratory and the surrounding community, scientists are busy sampling the air for chemicals and radiological materials. (Jae C. Hong/Associated Press) #

Michael Morgan hangs out in the Red Cross evacuation center set up at the Santa Claran Hotel in Espanola, N.M., on June 28, 2011, after evacuating from Los Alamos because of the Las Conchas fire. (Eddie Moore/Albuquerque Journal via Associated Press) #

The Las Conchas fire burns trees and grass near Los Alamos, N.M., on June 29, 2011. As crews fight to keep the wildfire from reaching the country's premier nuclear-weapons laboratory and the surrounding community, scientists are busy sampling the air for chemicals and radiological materials. (Jae C. Hong/Associated Press)#

A helicopter flies through the smoke from the Las Conchas fire in Los Alamos, N.M. on June 29, 2011. As crews fight to keep the wildfire from reaching the country's premier nuclear-weapons laboratory and the surrounding community, scientists are busy sampling the air for chemicals and radiological materials. (Jae C. Hong/Associated Press) #

The sun shines through smoke from the Las Conchas wildfire near the Los Alamos National Laboratory., on June 29, 2011. Thousands of residents calmly fled the town that's home to the Los Alamos nuclear laboratory as the rapidly growing wildfire approached, sending up towering plumes of smoke, raining down ash, and charring the fringes of the sprawling lab's property. The blaze, which began Sunday, had already destroyed 30 structures south of Los Alamos and forced the closure of the lab. (Eric Draper/Reuters) #